Usage

Arguments

an open connection or (for serialize)
NULL or (for unserialize) a raw vector
(see ‘Details’).

ascii

a logical. If TRUE or NA, an ASCII
representation is written; otherwise (default) a binary one.
See also the comments in the help for save.

xdr

a logical: if a binary representation is used, should a
big-endian one (XDR) be used?

version

the workspace format version to use. NULL
specifies the current default version (2), which has been the default
since R 1.4.0. The only other supported value is 3, introduced in
R 3.5.0.

refhook

a hook function for handling reference objects.

Details

The function serialize serializes object to the specified
connection. If connection is NULL then object is
serialized to a raw vector, which is returned as the result of
serialize.

Sharing of reference objects is preserved within the object but not
across separate calls to serialize.

unserialize reads an object (as written by serialize)
from connection or a raw vector.

The refhook functions can be used to customize handling of
non-system reference objects (all external pointers and weak
references, and all environments other than namespace and package
environments and .GlobalEnv). The hook function for
serialize should return a character vector for references it
wants to handle; otherwise it should return NULL. The hook for
unserialize will be called with character vectors supplied to
serialize and should return an appropriate object.

For a text-mode connection, the default value of ascii is set
to TRUE: only ASCII representations can be written to text-mode
connections and attempting to use ascii = FALSE will throw an
error.

The format consists of a single line followed by the data: the first
line contains a single character: X for binary serialization
and A for ASCII serialization, followed by a new line. (The
format used is identical to that used by readRDS.)

As almost all systems in current use are little-endian, xdr =
FALSE can be used to avoid byte-shuffling at both ends when
transferring data from one little-endian machine to another (or
between processes on the same machine). Depending on the system, this
can speed up serialization and unserialization by a factor of up to
3x.

Value

For serialize, NULL unless connection = NULL, when
the result is returned in a raw vector.

For unserialize an R object.

Warning

These functions have provided a stable interface since R 2.4.0 (when
the storage of serialized objects was changed from character to raw
vectors). However, the serialization format may change in future
versions of R, so this interface should not be used for long-term
storage of R objects.

On 32-bit platforms a raw vector is limited to 2^31 -
1 bytes, but R objects can exceed this and their serializations will
normally be larger than the objects.

See Also

saveRDS for a more convenient interface to serialize an
object to a file or connection.